Keeping Sanders' coalition of young people and first-time voters will be no easy task.

Young voters, who have come out in droves to back Sanders' candidacy, clamor for a chance to shake his hand.David McNew/Getty Images

Former presidential candidates like Howard Dean — who pioneered online fundraising and ignited progressives, but ultimately came up short in his 2004 presidential primary bid — saw their coalitions largely fracture after their presidential campaigns came to a close.

Even President Barack Obama — whose base of young voters, minorities and women came out in droves in his 2008 and 2012 presidential campaigns — struggled to get them to vote in off-year elections. That led to devastating losses in all levels of government during Obama's presidency, in which Democrats lost control of both the House and the Senate, adding to the gridlock in Washington, D.C.

Some Democrats remain skeptical of Sanders' ability to keep his base of young voters, as well as liberal-leaning independents, together.

"I'm not quite sure if there's an attachment to Bernie's issues, or the fact that a lot of his millions voters just don't like people that they perceive as of the current system. So we just don't know yet," Democratic political strategist Tom Bowen said in an interview. "But there are not a lot of examples of real movements created by leaders or candidates that sustain themselves," added Bowen, who has worked on every level of campaigns, from local races to Obama's presidential bid.

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Still, Democrats say there are ways Sanders can take advantage of his celebrity to enact the kind of changes he's been pushing for throughout his lifetime.

Here's a blueprint for Sanders' post-primary plans.

Capitalize early on his political capital

At no other time in Sanders' life will he wield more power than he does now.

Democratic Party leaders are now dependent on Sanders to help unify the party behind Clinton and elect Democrats up and down the ballot in 2016.

And that gives him leverage to gain quick victories toward his mission to achieve progressive goals.

"He probably, today, has more political capital than he's had at any point of the campaign. And every day that goes by, he loses a little bit of it," Steve Schale, a Florida Democrat who was a senior adviser to Obama's 2012 re-election operation in the Sunshine State, said in an interview. "Once he gets to June 7, if he doesn't have a plan, at that point he's just a guy who's lost."

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Sanders has already begun to cash in on that power, directing his millions of campaign contributors to donate to a handful of down-ballot congressional and state legislative candidates who share his political worldview.

Getting those types of candidates elected will help grow support for his policies in legislative bodies that can enact the kind of change Sanders seeks. And having a contingent of supporters in elected office will make him a more powerful actor moving forward.

Create a focused mission statement

And while a broad-based platform works in a presidential campaign, choosing to create a group focusing on all of those issues post-primary could lead to an unfocused message that may ultimately splinter his base and lead his revolution fizzle.

Democratic strategists say Sanders could start his own group with a narrowly tailored focus on income inequality or Wall Street reform, or lend his name and fundraising apparatus to other groups that have already laid the groundwork on other issues close to his heart.

Set achievable goals and build on them

With hard feelings among Sanders faithfuls sure to linger after his primary loss, Sanders should create goals guaranteed to give tangible results to his supporters, as further losses could disillusion his passionate base.

"Bernie sold revolution, so an amendment to the Democratic Party platform isn't going to be enough," Bowen said. "They have to go get real, measurable success. And I think that's endorsing or supporting candidates who will fight for working class people or bring a little more fairness to corporate America."